1. Field of the Invention
This invention relates to a tape recorder in which the sensitivity of sound recording and the degree of recorded sound compensation can be automatically adjusted to be optimum depending on the type of a magnetic tape used for sound recording.
2. DESCRIPTION OF THE PRIOR ART
Tape recorders, especially, so-called cassette deck type ones have progressively been gaining popularity among many audio fans as a music source of audio apparatus. This is attributable principally to the improved performance of the cassette decks and also to the improved performance of the cassette tapes.
The cassette tapes presently available in the market are broadly classified into the normal type, the chrome (CrO.sub.2) type, and the ferrichrome (FeCr) type. However, even the cassette tapes of the same type have different sound recording sensitivities and frequency characteristics depending on the maker, tape thickness, lot and other factors. Therefore, in order for the cassette tapes to exhibit their full performance, the sound recording sensitivity and frequency characteristic of each individual cassette tape must be adjusted to be optimum for the purpose of sound recording.
It has been a common practice in the prior art cassette decks that the sound recording sensitivity is optimized by manually adjusting the gain of the sound recording amplifier, and the frequency characteristic is optimized by changing over the equalizer by a change-over switch to one of the three stages depending on the type of the cassette tape. In one of the prior art cassette decks, a knob capable of fine adjustment of the equalization curve in the high frequency range of sound recording is provided so as to substantially flatten the frequency characteristic.
However, the provision of such a simple change-over switch and such a fine adjusting knob has not been completely successful for the desired exhibition of the full performance of the cassette tape.